SEMINAR SERIES ON
STRING PHENOMENOLOGY
SEMINAR SERIES ON
STRING PHENOMENOLOGY
Schedule: Winter Term 2026-27
The seminars are taking place on Zoom every second Tuesday at 11 am (all times in US Eastern Time Zone).
The Seminar Series on String Phenomenology will resume on October 6.
October 6
Alessandro Manta (University of Vienna):
Quantum Spacetimes and Gravity in IKKT matrix model
In this talk I will explain how the IKKT matrix model can be interpreted as a theory of quantum gravity. IKKT is a non-perturbatively defined model of quantum gravity, conjecturally of type IIB superstring theory, which studies quantum dynamics of quantized (noncommutative) spacetimes, represented as matrix configurations. I will explain how the weakly coupled regime of a 4d spacetime with fuzzy extra dimensions contains a Yang-Mills sector, and an Einstein-Hilbert sector at one-loop. Furthermore, for a class of solutions of IKKT, Covariant Quantum Spacetimes, we study the stability of these backgrounds coupled to extra dimensions. Lastly, we discuss how one-loop quantum effects affect these backgrounds.
Jarod Hattab (Ben-Gurion University):
Instanton Interactions and the Axion Weak Gravity Conjecture.
The Weak Gravity Conjecture admits a formulation in terms of long-range charged particle self-interactions being repulsive. We adopt a similar approach to the Axionic Weak Gravity Conjecture by considering long-range instanton interactions. At leading order, in the instanton separation, such interactions are mediated purely by massless scalar fields. Gravitational and gauge interactions are sub-leading. We formulate a repulsive interaction Axionic Weak Gravity Conjecture, which forms a bound on the scalar field dependence of the complex Euclidean instanton action. We show that in standard ultraviolet complete examples, this bound implies the usual formulation of the Axionic Weak Gravity Conjecture, while generally being stronger. Because this formulation is purely a statement about massless scalar fields, it implies that in the absence of massless scalars the usual bound on the axion decay constant could be modified.
October 20
Vittorio Larotonda (University of Bologna):
TBA
TBA
Subham Roy (SUNY Albany):
TBA.
TBA.
November 03
Michelangelo Tartaglia (IFT Madrid):
TBA
TBA
Luca Novelli (University of Bonn):
TBA.
TBA.